BOSTON (WJZ) — The FBI is following new leads in the Boston Marathon bombings. Those leads come as a boxing coach who knew one of the suspects speaks out for the first time.

Derek Valcourt has that interview with the coach and the latest on the bombing investigation.

Sources tell CBS News female DNA has been found on a bomb fragment recovered in Boston. Authorities are looking into whether the DNA came from a bombing victim or a female accomplice.

Sources tell CBS News FBI agents met with Katherine Russell, widow of accused bomber Tamerlan Tsarnaev, to collect a DNA sample so they can compare it against the DNA found on the bomb remnant to determine if she ever came in contact with the device and to question her whether she had any knowledge of the alleged plan by her husband.

Entertainment Tonight aired never-before-seen footage of the dead bombing suspect four years before the bombing, when Tamerlan was just 22 years old and working with boxing trainer John Allen.

Shortly after the footage was shot, Tamerlan’s life would change forever when in 2010 as reigning champ, he was disqualified from competition because they suddenly changed the rules about U.S. citizenship, bringing his Olympic dreams to a grinding halt.

“He was disillusioned in the sense that Massachusetts could have done more for him. They wanted to send the good old American boy instead of him and that was his interpretation of what really happened,” Allen said.

Allen says after the rules changed, Tamerlan soon began praying in the gym, becoming more religious as time went on.

“I will say that there were a couple of members who thought that he might be [a terrorist],” Allen said. “When he began to pray face toward Mecca and pray, right away you heard comments. `Is this guy a terrorist? I think this guy’s a terrorist,'” he said.

The FBI is also looking into Tamerlan Tsarnaev’s six month visit to Russia and Dagestan last year to determine if he received any training from known terrorists.

The surviving bombing suspect, Dzhokhar Tsarnaev, remains locked up in isolation in Massachusetts and has not spoken to investigators since he was read his rights last week.